In which situation is it NOT possible to achieve a pressure compensation between the middle ear and the environment?

Question

Question PPL(H) - Private Pilot License - Human Performance and limitations

QuizVDS · Accepted Answer

The eustachien tube is blocked

QuizVDS · Answer

All windows are completely closed

QuizVDS · Answer

Breathing takes place using the mouth only

QuizVDS · Answer

During a light and slow climb

Id 338 - PPL(H) EN - In which situation is it NOT possible to achieve a pressure compensation between the middle ear and the environment?